Process of and means for covering the parts of an aircraft



United States Patent 3,330,710 PROCESS OF AND MEANS FOR COVERING THEPARTS OF AN AIRCRAFT Paul F. Lloyd and Samuel J. Macre, Blytheville,Ark., assignors to Razorback Fabrics, Inc., Manila, Ark., a corporationof Arkansas No Drawing. Continuation of abandoned application Ser. No.213,625, July 31, 1962. This application Mar. 1, 1966, Ser. No. 530,791

1 Claim. (Cl. 156-85) glass fibers as a reinforcing material mountedupon the conventional cotton and linen fabrics. It is applicantsunderstanding that innumerable attempts have been made by many skilledin the art to produce a covering for parts of aircraft consisting offiber glass fabric without the use of any conventional cotton or linencovering, and that all such attempts have been completely unsuccessful.

However, as a result of abundant exhaustive tests, we discovered ournovel use of the particular woven fabric consisting of glass fibers,without the use of any conventional cotton or linen covering to producethe required covering. We were enabled to successfully practice ournovel process by the combined use of the particular glass fiber fabricand a particular dope.

The particular fabric of glass fibers used is constructed withspecifications as follows: thread count 36 x 34 per square inch, warpyarn 450/2/2, filling yarn 450/2/2, average thickness in mills 5.0,average weight per square yard 3.92 ounces, minimum average breakingstrength per square inch 160x 150 pounds, weave plain.

The particular dope used is a solution of cellulose acetate butyratehaving 12% solids and a solvent.

We discovered that, when the above described fabric was treated with aseries of applications of the above described dope, a completelysatisfactory covering was produced. Hence, it is obvious that the novelmeans whereby our process has been successfully practiced is theheretofore unknown combination of the particular glass fiber fabric andthe particular dope.

Our novel process consists in the following steps:

We measure the surface of each part of the aircraft which is to becovered. We then cut pieces of the fabric to fit each of said parts ofthe aircraft surface. We place each cut piece of the fabric on itsproper part of the surface, under such tension as to remove all wrinklesfrom the piece of fabric. We then apply to each placed piece of fabric asolution of cellulose acetate butyrate dope having 12% solids and asolvent, holding each piece of fabric in proper position until the dopehas dried by evaporation of its solvent and the piece of fabric hasadhered to the part of the aircraft on which it has been placed. We thenapply to each piece of fabric sufiicient coats of the dope of 12% solidsas to cause complete penetration of said solids of said dope remainingafter the solvent has evaporated, through the weave of the fabric 3,330]10' Patented July 1 l 1 967 ice as to fill all spaces between thethreads of the fabric remaining after the evaporation of the solvent,thereby producing an integrated, pliable mass in which the fibers areanchored. We then apply sufiicient additional coats of the dope toeffect the final satisfactory degree of tautness of the treated fabric.

The said fabric pieces are thus applied and adhered to the stringers ofthe fuselage, the ribs of the wings and empennage. After the severalportions of the fabric have been thus mounted, all overlapped jointsthereof are taped with suitable strips of said glass fiber fabric andadhered thereto.

We discovered that this penetration of the dope into the fabric effectsthe heretofore unknown result of the production of the solid mass ofresidue of the dope in which the individual fibers of the fabric areanchored so as to product the integrated mass. It is to be understoodthat such a mass has the desired degree of pliability.

We discovered that a sufiicient number of additional applications of thedope so affected this integrated mass as to produce the finalsatisfactory degree of tautness of the covering. It has been ourexperience that the satisfactory practice of our novel process issecured by at least four applications of the dope, to produce theintegrated mass, and four further applications to secure the finaldegree of tautness.

The immense value of our invention is based upon the followingfundamental characteristic which differentiate our improved coveringfrom the conventional covering composed of cotton or linen:

Our improved covering comprising the integrated mass of fiber glassfabric and dope is resistant to weather conditions, decay or chemicaldamage. It is fire resistant. It has a safety factor, proven byexhaustive tests, such as its'tensile strength exceeding over 100 poundsas against pounds for cotton fabric; tear test 12 pounds, as againstcotton 5 pounds.

Moreover, experience has shown that cotton covering requires from 12 to15 applications of dope to produce an opaque coating, to preventdeterioration of the coating by light, while our covering, beingresistant to light, requires no such opacity. We have found that ourcovering is far more economical in initial cost of material andmaintenance than the conventional cotton and linen.

Applicants have herein disclosed a novel method for covering par-ts ofan aircraft which comprises placing on the aircraft surface the peculiarwoven fabric having the characteristics hereinbefore enumerated, andthen treating the fabric as hereinbefore described with a dope havingthe hereinbefore described characteristics, that said dope penetratingthe weave of said fabric produces an integrated mass to anchor thefibers of the fabric.

It is believed that the prior art does not disclose either the identicalor any equivalent process whereby such a covering can be produced.

Having described our invention, what we claim is:

A process of covering the parts of an aircraft which comprises measuringthe surface of each part to be covered, cutting a piece of woven fiberglass fabric to fit said surface, placing said piece of fabric on saidsurface under tension to remove all wrinkles, applying to said piece offabric a coating of cellulose acetate butyrate dope having 12% solidsand a solvent, holding said piece of fabric in position until the dopehas dried by evaporation of the solvent and the piece of fabric adheresto the surface on which it is placed, applying suflicient coats of saiddope to said piece of fabric as to give complete penetration of saidsolids remaining after the solvent has evaporated, through the weave ofthe fabric as to fill all 3 4- spaces between the fibers of said fabric,thereby producing References Cited an integrated, pliable mass in whichsaid fibers are an- UNITED STATES PATENTS chored, and applyingsufficient additional coats of said dope to said piece of fabric as toeffect the final satis- 2 014068 9/1935 Hutchman 117-7 factory degree oftautness of said piece of fabric, said 5 2,215,061 9/ 1940 Alt 161-201 Xwoven fiber glass fabric consisting of impermeable glass FOREIGN PATENTSthreads having a thread count of 36 X 34 per square inch, 11 981 9 1944A warp thread 450/2/2, filling yarn 450/2/2, thickness in rnills 5.0,weight per square yard 3.92 ounces, minimum v average breaking strengthper square inch 160x 150, 10 EARL M'BERGERTP'lmary Exammer' weave plain.P. DIER, Assistant Examiner.

